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Synthesis 2003(2): 0223-0226
DOI: 10.1055/s-2003-36834
DOI: 10.1055/s-2003-36834
PAPER
© Georg Thieme Verlag Stuttgart · New York
Synthesis of 6,6-Difluorohomopiperazines via Microwave-Assisted Detosylation
Further Information
Received
22 July 2002
Publication Date:
22 January 2003 (online)
Publication History
Publication Date:
22 January 2003 (online)
Abstract
[1,4]-Diazepan-6-ols are easily oxidized to ketones using Swern or Dess-Martin oxidation conditions. The fluorination of these [1,4]-diazepanones with diethylaminosulfur trifluoride (DAST) affords gem-difluorohomopiperazines. Detosylation under microwave conditions represents a rapid method to access the corresponding amines in high yields.
Key words
heterocycles - sulfonamides - protecting groups - diethylaminosulfur trifluoride (DAST) - microwaves
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